Peel the taro and purple sweet potato and cut them into pieces.

Steam until completely tender. They should be soft enough to mash easily with a fork.

Weigh 250 g cooked taro and 250 g cooked purple sweet potato.

Blend until very smooth.

Try not to add extra water. If your blender has difficulty processing the mixture, add only a small amount at a time.

Add the vegetable oil and blend again until completely incorporated.

Mix the flour with 20 g water until smooth, then add it to the filling.

Transfer the mixture to a wide microwave-safe bowl.

Microwave at approximately 700–800 W for 2 minutes, then remove and stir thoroughly.

Continue cooking in 2-minute intervals at first, stirring between each round.

As the filling thickens, reduce the intervals to 1 minute.

The filling is ready when it forms a soft, cohesive mass that holds its shape.

Don't make it too dry while it is hot. The taro, sweet potato and coconut will continue to absorb moisture as the filling cools.

Let the filling cool completely before weighing and rolling it into balls.

Combine the golden syrup, custard powder, egg yolk and vegetable oil in a mixing bowl.

Mix until smooth and evenly combined.

Add 165 g cake flour and gently mix with a spatula until a soft dough forms.

At this stage, don't automatically add all of the additional flour. Different brands of flour absorb liquid differently.

Cover the dough and let it rest for approximately 30–45 minutes.

After resting, check the consistency. If the dough is still too sticky to work with, add additional cake flour gradually until it becomes soft, smooth and manageable.

Avoid adding too much flour. The dough should remain supple enough to stretch around the filling without cracking.

Also avoid kneading it like bread dough. Mix only as much as necessary to bring everything together.

Mix gently until combined.

Try not to whisk vigorously because you don't want lots of bubbles in the egg wash.

Make sure both the filling and dough are completely cool before assembling.

Divide the filling into balls according to the size of your mooncake mould.

For a classic thin-skinned baked mooncake, I like approximately 30% dough to 70% filling.

For example:

100 g mooncake: approximately 30 g dough + 70 g filling.

75 g mooncake: approximately 23 g dough + 52 g filling.

The exact ratio can be adjusted depending on your mould and how comfortable you are wrapping a thin mooncake skin.

Roll a portion of dough into a ball and gently flatten it into a disc.

Place the filling in the centre.

Slowly push and stretch the dough upward around the filling until it is completely enclosed. Pinch the seam closed and gently roll it into a smooth ball.

Lightly dust the mooncake and mould with cake flour, shaking off all excess flour.

Place the ball into the mooncake mould and press firmly onto a lined baking tray.

Carefully release the mould.

Preheat the oven to 180°C.

Lightly mist the mooncakes with water before baking if desired.

Bake for approximately 8–10 minutes, just until the crust has set and the pattern is firm.

Remove from the oven and allow the mooncakes to cool for approximately 10–15 minutes.

Brush a very thin layer of egg wash over the surface. Don't allow egg wash to pool inside the detailed patterns of the mould.

Return to the oven and continue baking until the mooncakes are evenly golden, approximately another 10–15 minutes, depending on your oven and the size of the mooncakes.

Keep an eye on them towards the end because the egg-washed surface can brown quickly.